Abstract [en]

The objective of this study was to compare the effect of two different degrees of mandibular advancement (MA), 75% versus 50%, on somnographic variables after 6 months of dental appliance treatment in patients with severe obstructive sleep apnea (OSA). A further purpose was to compare the number of adverse events on the stomatognathic system and the effects of dental appliance treatment on the presence of daytime sleepiness.

Eighty-six males with severe OSA (apnea index ≥ 20) were randomly allocated to either 75% or 50% MA. Forty patients in the 75% MA group and 37 patients in the 50% MA group completed the 6-month follow-up.

The effectiveness of treatment in terms of normalization (apnea index < 5 and apnea/hypopnea index < 10) with 75% MA was 52%, which was significantly higher (p = 0.04) than the 31% achieved with 50% MA. The dental appliance had few adverse events on the stomatognathic system regardless of group, and the number of adverse events did not differ between the two groups. Finally, the mean value of Epworth Sleepiness Scale scores decreased significantly from 11.6 at baseline to 8.0 at follow-up (p < 0.001). No significant difference was observed between the two groups. The results indicate that a dental appliance could be an alternative treatment for some patients with severe OSA.

Walker-Engström, Marie-Louise

Uppsala University, Interfaculty Units, Centre for Clinical Research.

2003 (Swedish)Doctoral thesis, comprehensive summary (Other academic)

Abstract [en]

Enthusiasm for uvulopalatopharyngoplasty (UPPP) in the treatment of mild-to-moderate obstructive sleep apnea syndrome (OSAS) has declined in recent years, partly because of a lower success rate over time and partly because of adverse effects. In more severe cases, the patients are generally treated with nasal continuous positive airway pressure (CPAP). However, many patients do not satisfactorily tolerate CPAP as a result of frequent side-effects. Consequently, there is a need for an alternative treatment. Reports on the beneficial effects of mandibular advancement appliances in the treatment of mild-to-moderate OSA exist in the form of short–term evaluations.

One of the aims of the present thesis was to compare treatment effects with a mandibular advancement appliance and UPPP in patients with OSA with follow-up after one and four years. Ninety-five male patients with confirmed mild-to-moderate OSA (apnea index, AI >5 and <25) were randomised to treatment with a dental appliance or UPPP. Sleep studies were performed before and one and four years after intervention. According to the criteria for normalisation (AI<5 and apnea hypopnea index, AHI<10), 78% of the patients in the dental appliance group and 51% of the patients in the UPPP group had normalised after one year (p<0.05). Still after four years of treatment, 63% of the patients in the dental appliance group and 33% of the patients in the UPPP group were normalised. The dental appliance group had a higher normalisation rate than the UPPP group, but the efficacy was partly invalidated by the compliance rate of 62%.

Quality of life assessments in the dimensions of vitality, contentment and sleep improved in both groups at the one-year follow-up after treatment. There was no difference between the groups in terms of vitality and sleep. The UPPP group, however, reported a higher degree of contentment than the dental appliance group, even though the somnographic values were superior in the latter group.

Another aim was to conduct a randomised study to test the hypothesis that severe OSA patients will benefit from more pronounced mandibular advancement (MA) compared with a shorter advancement. Eighty-six males with severe OSA (AI>20) were randomly allocated to either 75% or 50% MA for a six-month treatment period. Treatment with a more pronounced mandibular advancement yielded a 20% higher normalisation rate than a shorter advancement. A mean normalisation rate of 45% was found for patients in this category with few side-effects, good patient satisfaction and a compliance of 92% after 6 months.

The overall conclusion is that dental appliance treatment is effective in patients with mild to moderate OSA and even for patients with severe OSA. The efficacy in terms of normalisation in patients with mild to moderate OSA was higher after the dental appliance treatment with a 50% degree of advancement than after the UPPP treatment. However, severe OSA patients might benefit from more pronounced advancement (75%) compared with a shorter degree of advancement (50%). QOL improved significantly after both dental appliance and UPPP treatment.